/*************************************************************************
Title:    Interrupt UART library with receive/transmit circular buffers
Author:   Peter Fleury <pfleury@gmx.ch>   http://jump.to/fleury
File:     $Id: uart.c,v 1.6.2.2 2009/11/29 08:56:12 Peter Exp $
Software: AVR-GCC 4.1, AVR Libc 1.4.6 or higher
Hardware: any AVR with built-in UART,
License:  GNU General Public License

DESCRIPTION:
    An interrupt is generated when the UART has finished transmitting or
    receiving a byte. The interrupt handling routines use circular buffers
    for buffering received and transmitted data.

    The UART_RX_BUFFER_SIZE and UART_TX_BUFFER_SIZE variables define
    the buffer size in bytes. Note that these variables must be a
    power of 2.

USAGE:
    Refere to the header file uart.h for a description of the routines.
    See also example test_uart.c.

NOTES:
    Based on Atmel Application Note AVR306

LICENSE:
    Copyright (C) 2006 Peter Fleury

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

*************************************************************************/
#include "main.h"
#include "uart.h"


/*
 *  constants and macros
 */

/* size of RX/TX buffers */
#define UART_RX_BUFFER_MASK ( UART_RX_BUFFER_SIZE - 1)
#define UART_TX_BUFFER_MASK ( UART_TX_BUFFER_SIZE - 1)

#if ( UART_RX_BUFFER_SIZE & UART_RX_BUFFER_MASK )
#error RX buffer size is not a power of 2
#endif
#if ( UART_TX_BUFFER_SIZE & UART_TX_BUFFER_MASK )
#error TX buffer size is not a power of 2
#endif

#if defined(__AVR_AT90S2313__) \
 || defined(__AVR_AT90S4414__) || defined(__AVR_AT90S4434__) \
 || defined(__AVR_AT90S8515__) || defined(__AVR_AT90S8535__) \
 || defined(__AVR_ATmega103__)
 /* old AVR classic or ATmega103 with one UART */
 #define AT90_UART
 #define UART0_RECEIVE_INTERRUPT   SIG_UART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_UART_DATA
 #define UART0_STATUS   USR
 #define UART0_CONTROL  UCR
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE
#elif defined(__AVR_AT90S2333__) || defined(__AVR_AT90S4433__)
 /* old AVR classic with one UART */
 #define AT90_UART
 #define UART0_RECEIVE_INTERRUPT   SIG_UART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_UART_DATA
 #define UART0_STATUS   UCSRA
 #define UART0_CONTROL  UCSRB
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE
#elif  defined(__AVR_ATmega8__)  || defined(__AVR_ATmega16__) || defined(__AVR_ATmega32__) \
  || defined(__AVR_ATmega8515__) || defined(__AVR_ATmega8535__) \
  || defined(__AVR_ATmega323__)
  /* ATmega with one USART */
 #define ATMEGA_USART
 #define UART0_RECEIVE_INTERRUPT   SIG_UART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_UART_DATA
 #define UART0_STATUS   UCSRA
 #define UART0_CONTROL  UCSRB
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE


#elif defined(__AVR_ATmega163__)
  /* ATmega163 with one UART */
 #define ATMEGA_UART
 #define UART0_RECEIVE_INTERRUPT   SIG_UART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_UART_DATA
 #define UART0_STATUS   UCSRA
 #define UART0_CONTROL  UCSRB
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE
#elif defined(__AVR_ATmega162__)
 /* ATmega with two USART */
 #define ATMEGA_USART0
 #define ATMEGA_USART1
 #define UART0_RECEIVE_INTERRUPT   SIG_USART0_RECV
 #define UART1_RECEIVE_INTERRUPT   SIG_USART1_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_USART0_DATA
 #define UART1_TRANSMIT_INTERRUPT  SIG_USART1_DATA
 #define UART0_STATUS   UCSR0A
 #define UART0_CONTROL  UCSR0B
 #define UART0_DATA     UDR0
 #define UART0_UDRIE    UDRIE0
 #define UART1_STATUS   UCSR1A
 #define UART1_CONTROL  UCSR1B
 #define UART1_DATA     UDR1
 #define UART1_UDRIE    UDRIE1
#elif defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
 /* ATmega with two USART */
 #define ATMEGA_USART0
 #define ATMEGA_USART1
 #define UART0_RECEIVE_INTERRUPT   SIG_UART0_RECV
 #define UART1_RECEIVE_INTERRUPT   SIG_UART1_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_UART0_DATA
 #define UART1_TRANSMIT_INTERRUPT  SIG_UART1_DATA
 #define UART0_STATUS   UCSR0A
 #define UART0_CONTROL  UCSR0B
 #define UART0_DATA     UDR0
 #define UART0_UDRIE    UDRIE0
 #define UART1_STATUS   UCSR1A
 #define UART1_CONTROL  UCSR1B
 #define UART1_DATA     UDR1
 #define UART1_UDRIE    UDRIE1
#elif defined(__AVR_ATmega161__)
 /* ATmega with UART */
 #error "AVR ATmega161 currently not supported by this libaray !"
#elif defined(__AVR_ATmega169__)
 /* ATmega with one USART */
 #define ATMEGA_USART
 #define UART0_RECEIVE_INTERRUPT   SIG_USART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_USART_DATA
 #define UART0_STATUS   UCSRA
 #define UART0_CONTROL  UCSRB
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE
#elif defined(__AVR_ATmega48__) ||defined(__AVR_ATmega88__) || defined(__AVR_ATmega168__) || defined(__AVR_ATmega48P__) || defined(__AVR_ATmega88P__) || defined(__AVR_ATmega168P__) || defined(__AVR_ATmega328P__) || defined(__AVR_ATmega328__)
 /* ATmega with one USART */
 #define ATMEGA_USART0
 #define UART0_RECEIVE_INTERRUPT   USART_RX_vect
 #define UART0_TRANSMIT_INTERRUPT  USART_UDRE_vect
 #define UART0_STATUS   UCSR0A
 #define UART0_CONTROL  UCSR0B
 #define UART0_DATA     UDR0
 #define UART0_UDRIE    UDRIE0
#elif defined(__AVR_ATtiny2313__)
 #define ATMEGA_USART
 #define UART0_RECEIVE_INTERRUPT   SIG_USART0_RX
 #define UART0_TRANSMIT_INTERRUPT  SIG_USART0_UDRE
 #define UART0_STATUS   UCSRA
 #define UART0_CONTROL  UCSRB
 #define UART0_DATA     UDR
 #define UART0_UDRIE    UDRIE
#elif defined(__AVR_ATmega329__) ||defined(__AVR_ATmega3290__) ||\
      defined(__AVR_ATmega649__) ||defined(__AVR_ATmega6490__) ||\
      defined(__AVR_ATmega325__) ||defined(__AVR_ATmega3250__) ||\
      defined(__AVR_ATmega645__) ||defined(__AVR_ATmega6450__)
  /* ATmega with one USART */
  #define ATMEGA_USART0
  #define UART0_RECEIVE_INTERRUPT   SIG_UART_RECV
  #define UART0_TRANSMIT_INTERRUPT  SIG_UART_DATA
  #define UART0_STATUS   UCSR0A
  #define UART0_CONTROL  UCSR0B
  #define UART0_DATA     UDR0
  #define UART0_UDRIE    UDRIE0
#elif defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__) || defined(__AVR_ATmega1280__)  || defined(__AVR_ATmega1281__) || defined(__AVR_ATmega640__)
/* ATmega with two USART */
  #define ATMEGA_USART0
  #define ATMEGA_USART1
  #define UART0_RECEIVE_INTERRUPT   SIG_USART0_RECV
  #define UART1_RECEIVE_INTERRUPT   SIG_USART1_RECV
  #define UART0_TRANSMIT_INTERRUPT  SIG_USART0_DATA
  #define UART1_TRANSMIT_INTERRUPT  SIG_USART1_DATA
  #define UART0_STATUS   UCSR0A
  #define UART0_CONTROL  UCSR0B
  #define UART0_DATA     UDR0
  #define UART0_UDRIE    UDRIE0
  #define UART1_STATUS   UCSR1A
  #define UART1_CONTROL  UCSR1B
  #define UART1_DATA     UDR1
  #define UART1_UDRIE    UDRIE1
#elif defined(__AVR_ATmega644__)
 /* ATmega with one USART */
 #define ATMEGA_USART0
 #define UART0_RECEIVE_INTERRUPT   SIG_USART_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_USART_DATA
 #define UART0_STATUS   UCSR0A
 #define UART0_CONTROL  UCSR0B
 #define UART0_DATA     UDR0
 #define UART0_UDRIE    UDRIE0
#elif defined(__AVR_ATmega164P__) || defined(__AVR_ATmega324P__) || defined(__AVR_ATmega644P__)
 /* ATmega with two USART */
 #define ATMEGA_USART0
 #define ATMEGA_USART1
 #define UART0_RECEIVE_INTERRUPT   SIG_USART_RECV
 #define UART1_RECEIVE_INTERRUPT   SIG_USART1_RECV
 #define UART0_TRANSMIT_INTERRUPT  SIG_USART_DATA
 #define UART1_TRANSMIT_INTERRUPT  SIG_USART1_DATA
 #define UART0_STATUS   UCSR0A
 #define UART0_CONTROL  UCSR0B
 #define UART0_DATA     UDR0
 #define UART0_UDRIE    UDRIE0
 #define UART1_STATUS   UCSR1A
 #define UART1_CONTROL  UCSR1B
 #define UART1_DATA     UDR1
 #define UART1_UDRIE    UDRIE1
#else
 #error "no UART definition for MCU available"
#endif


/*
 *  module global variables
 */
static volatile unsigned char UART_TxBuf[UART_TX_BUFFER_SIZE];
static volatile unsigned char UART_RxBuf[UART_RX_BUFFER_SIZE];
static volatile unsigned char UART_TxHead;
static volatile unsigned char UART_TxTail;
static volatile unsigned char UART_RxHead;
static volatile unsigned char UART_RxTail;
static volatile unsigned char UART_LastRxError;

#if defined( ATMEGA_USART1 )
static volatile unsigned char UART1_TxBuf[UART_TX_BUFFER_SIZE];
static volatile unsigned char UART1_RxBuf[UART_RX_BUFFER_SIZE];
static volatile unsigned char UART1_TxHead;
static volatile unsigned char UART1_TxTail;
static volatile unsigned char UART1_RxHead;
static volatile unsigned char UART1_RxTail;
static volatile unsigned char UART1_LastRxError;
#endif



SIGNAL(UART0_RECEIVE_INTERRUPT)
/*************************************************************************
Function: UART Receive Complete interrupt
Purpose:  called when the UART has received a character
**************************************************************************/
{
    unsigned char tmphead;
    unsigned char data;
    unsigned char usr;
    unsigned char lastRxError;


    /* read UART status register and UART data register */
    usr  = UART0_STATUS;
    data = UART0_DATA;

    /* */
#if defined( AT90_UART )
    lastRxError = (usr & (_BV(FE)|_BV(DOR)) );
#elif defined( ATMEGA_USART )
    lastRxError = (usr & (_BV(FE)|_BV(DOR)) );
#elif defined( ATMEGA_USART0 )
    lastRxError = (usr & (_BV(FE0)|_BV(DOR0)) );
#elif defined ( ATMEGA_UART )
    lastRxError = (usr & (_BV(FE)|_BV(DOR)) );
#endif

    /* calculate buffer index */
    tmphead = ( UART_RxHead + 1) & UART_RX_BUFFER_MASK;

    if ( tmphead == UART_RxTail ) {
        /* error: receive buffer overflow */
        lastRxError = UART_BUFFER_OVERFLOW >> 8;
    }else{
        /* store new index */
        UART_RxHead = tmphead;
        /* store received data in buffer */
        UART_RxBuf[tmphead] = data;
    }
    UART_LastRxError = lastRxError;
}


SIGNAL(UART0_TRANSMIT_INTERRUPT)
/*************************************************************************
Function: UART Data Register Empty interrupt
Purpose:  called when the UART is ready to transmit the next byte
**************************************************************************/
{
    unsigned char tmptail;


    if ( UART_TxHead != UART_TxTail) {
        /* calculate and store new buffer index */
        tmptail = (UART_TxTail + 1) & UART_TX_BUFFER_MASK;
        UART_TxTail = tmptail;
        /* get one byte from buffer and write it to UART */         
        UART0_DATA = UART_TxBuf[tmptail];  /* start transmission */ 
    }else{                                                          
        /* tx buffer empty, disable UDRE interrupt */               
        UART0_CONTROL &= ~_BV(UART0_UDRIE);                         
    }
}


/*************************************************************************
Function: uart_init()
Purpose:  initialize UART and set baudrate
Input:    baudrate using macro UART_BAUD_SELECT()
Returns:  none
**************************************************************************/
void uart_init(unsigned int baudrate)
{
    UART_TxHead = 0;
    UART_TxTail = 0;
    UART_RxHead = 0;
    UART_RxTail = 0;

#if defined( AT90_UART )
    /* set baud rate */
    UBRR = (unsigned char)baudrate;

    /* enable UART receiver and transmmitter and receive complete interrupt */
    UART0_CONTROL = _BV(RXCIE)|_BV(RXEN)|_BV(TXEN);

#elif defined (ATMEGA_USART)
    /* Set baud rate */
    if ( baudrate & 0x8000 )
    {
    	 UART0_STATUS = (1<<U2X);  //Enable 2x speed
    	 baudrate &= ~0x8000;
    }
    UBRRH = (unsigned char)(baudrate>>8);
    UBRRL = (unsigned char) baudrate;

    /* Enable USART receiver and transmitter and receive complete interrupt */
    UART0_CONTROL = _BV(RXCIE)|(1<<RXEN)|(1<<TXEN);

    /* Set frame format: asynchronous, 8data, no parity, 1stop bit */
    #ifdef URSEL
    UCSRC = (1<<URSEL)|(3<<UCSZ0);
    #else
    UCSRC = (3<<UCSZ0);
    #endif

#elif defined (ATMEGA_USART0 )
    /* Set baud rate */
    if ( baudrate & 0x8000 )
    {
   		UART0_STATUS = (1<<U2X0);  //Enable 2x speed
   		baudrate &= ~0x8000;
   	}
    UBRR0H = (unsigned char)(baudrate>>8);
    UBRR0L = (unsigned char) baudrate;

    /* Enable USART receiver and transmitter and receive complete interrupt */
    UART0_CONTROL = _BV(RXCIE0)|(1<<RXEN0)|(1<<TXEN0);

    /* Set frame format: asynchronous, 8data, no parity, 1stop bit */
    #ifdef URSEL0
    UCSR0C = (1<<URSEL0)|(3<<UCSZ00);
    #else
    UCSR0C = (3<<UCSZ00);
    #endif

#elif defined ( ATMEGA_UART )
    /* set baud rate */
    if ( baudrate & 0x8000 )
    {
    	UART0_STATUS = (1<<U2X);  //Enable 2x speed
    	baudrate &= ~0x8000;
    }
    UBRRHI = (unsigned char)(baudrate>>8);
    UBRR   = (unsigned char) baudrate;

    /* Enable UART receiver and transmitter and receive complete interrupt */
    UART0_CONTROL = _BV(RXCIE)|(1<<RXEN)|(1<<TXEN);

#endif

}/* uart_init */


/*************************************************************************
Function: uart_getc()
Purpose:  return byte from ringbuffer
Returns:  lower byte:  received byte from ringbuffer
          higher byte: last receive error
**************************************************************************/
unsigned int uart_getc(void)
{
    unsigned char tmptail;
    unsigned char data;


    if ( UART_RxHead == UART_RxTail ) {
        return UART_NO_DATA;   /* no data available */
    }

    /* calculate /store buffer index */
    tmptail = (UART_RxTail + 1) & UART_RX_BUFFER_MASK;
    UART_RxTail = tmptail;

    /* get data from receive buffer */
    data = UART_RxBuf[tmptail];

    return (UART_LastRxError << 8) + data;

}/* uart_getc */


/*************************************************************************
Function: uart_putc()
Purpose:  write byte to ringbuffer for transmitting via UART
Input:    byte to be transmitted
Returns:  none
**************************************************************************/
void uart_putc(unsigned char data)
{
    unsigned char tmphead;


    tmphead  = (UART_TxHead + 1) & UART_TX_BUFFER_MASK;

    while ( tmphead == UART_TxTail ){
        ;/* wait for free space in buffer */
    }

    UART_TxBuf[tmphead] = data;
    UART_TxHead = tmphead;

    /* enable UDRE interrupt */
    UART0_CONTROL    |= _BV(UART0_UDRIE);

}/* uart_putc */


/*************************************************************************
Function: uart_puts()
Purpose:  transmit string to UART
Input:    string to be transmitted
Returns:  none
**************************************************************************/
void uart_puts(const char *s )
{
    while (*s)
      uart_putc(*s++);

}/* uart_puts */


/*************************************************************************
Function: uart_puts_p()
Purpose:  transmit string from program memory to UART
Input:    program memory string to be transmitted
Returns:  none
**************************************************************************/
void uart_puts_p(const char *progmem_s )
{
    register char c;

    while ( (c = pgm_read_byte(progmem_s++)) )
      uart_putc(c);                                                         
                                                                            
}/* uart_puts_p */                                                          
                                                                            
                                                                            
/*************************************************************************  
Function: uart_puthex_nibble()                                              
Purpose:  transmit lower nibble as ASCII-hex to UART                        
Input:    byte value                                                        
Returns:  none                                                              
**************************************************************************/ 
void uart_puthex_nibble(const unsigned char b)                              
{
	unsigned char  c = b & 0x0f;
	if ( c > 9 ) {
		c += 'A'-10;
	}
	else {
		c += '0';
	}
	uart_putc(c);
} /* uart_puthex_nibble */

/*************************************************************************
Function: uart_puthex_byte()
Purpose:  transmit upper and lower nibble as ASCII-hex to UART
Input:    byte value
Returns:  none
**************************************************************************/
void uart_puthex_byte( const unsigned char  b )
{
	uart_puthex_nibble( b >> 4 );
	uart_puthex_nibble( b );
} /* uart_puthex_byte */

/*************************************************************************
 Function: uart_puthex_16bit()
 Purpose:  transmit a 16bit value out UART as hexidary
 Input:    16bit value
 Returns:  none
 **************************************************************************/
void uart_puthex_short( const uint16_t lbyte )
{
	uart_puthex_byte( (unsigned char)( lbyte >> 8 ) );
	uart_puthex_byte( (unsigned char)( lbyte ) );
} /* uart_puthex_byte */

/*************************************************************************
Function: uart_puthex_long()
Purpose:  transmit unsigned long as ASCII-hex to UART
Input:    uint32_t value
Returns:  none
**************************************************************************/
void uart_puthex_long( const uint32_t l )
{
	uart_puthex_byte( (unsigned char)( l >> 24 ) );
	uart_puthex_byte( (unsigned char)( l >> 16 ) );
	uart_puthex_byte( (unsigned char)( l >> 8 ) );
	uart_puthex_byte( (unsigned char)( l ) );
} /* uart_puthex_byte */

/*************************************************************************
Function: uart_putbin_byte()
Purpose:  transmit a byte (8bit) as binary out UART
Input:    uint8_t value
Returns:  none
**************************************************************************/
void uart_putbin_byte(uint8_t c) {
    unsigned char i, j;
    j = 0b10000000;

    for (i = 0; i < 8; i++) {
        if (c & j) {
            uart_putc('1');
        } else {
        	uart_putc('0');
        }
        j >>= 1;
    }

}

/*************************************************************************
 Function: uart_putint_long
 Purpose:  Output a 32bit value int via UART
 Input:    uint32 value
 Returns:  none
 **************************************************************************/
void uart_putint_long(uint32_t l) {
    unsigned long c, m;
    unsigned char j, k = 0;

    c = 100000000;
    for (j = 0; j < 8; j++) {
        m = l / c;
        if (k || m) {
        	uart_putc(m + '0');
            l = l - (m * c);
            k = 1;
        }
        c /= 10;
    }
    uart_putc(l + '0');

}

/*************************************************************************
 Function: uart_putint_long_f
 Purpose:  Output a 32bit value intiger via UART (FANCY)
 Input:    uint32 value
 Returns:  none

 Long Description:
 This function differs from uart_putint_long because it outputs the intiger
 in a 'fancy' syntax. It includes ',' and leading '0's.
 **************************************************************************/
void uart_putint_long_f(uint32_t l) {
    unsigned long int temp;
    int mld, mil;

    mld = 0;
    mil = 0;
    temp = 0;

    if (l >= 1000000) {
        temp = l / 1000000;
        f_uiWdec_uint16(temp);
        uart_putc(',');
        l %= 1000000;
        if (l < 1000) uart_puts("000,");
        mld = 1;
        mil = 1;
    }
    if (l >= 1000) {
        temp = l / 1000;
        if (temp > 100) {
            f_uiWdec_uint16(temp);
        } else if (mld) {
            if (temp > 10) {
                uart_putc('0'); // 1 leading zero
            } else {
                uart_puts("00");
            }
            f_uiWdec_uint16(temp);
        } else f_uiWdec_uint16(temp);
        uart_putc(',');
        l %= 1000;
        mil = 1;
    }
    if (l > 100) {
        f_uiWdec_uint16(l);
    } else if (mil) {
        if (l > 10) {
            uart_putc('0'); // 1 leading zero
        } else {
            uart_puts("00");
        }
        f_uiWdec_uint16(l);
    } else f_uiWdec_uint16(l);
}

/*************************************************************************
 Function: uart_putint_16bit
 Purpose:  Output a 16bit value integer via UART
 Input:    uint16 value
 Returns:  none
 **************************************************************************/
void uart_putint_short(uint16_t i) {
    unsigned int c, m;
    unsigned char j, k = 0;

    c = 10000;
    for (j = 0; j < 4; j++) {
        m = i / c;
        if (k || m) {
            uart_putc(m + '0');
            i = i - (m * c);
            k = 1;
        }
        c /= 10;
    }
    uart_putc(i + '0');
}

/*************************************************************************
 Function: uart_putint_byte
 Purpose:  Output a byte long integer via UART
 Input:    uint8 value
 Returns:  none
 **************************************************************************/
void uart_putint_byte(uint8_t c)
{
    unsigned char d, j, m, k = 0;

    d = 100;
    for (j = 0; j < 2; j++) {
        m = c / d;
        if (k || m) {
            uart_putc(m + '0');
            c = c - (m * d);
            k = 1;
        }
        d /= 10;
    }
    uart_putc(c + '0');
}


